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1.
以苯乙烯-乙烯/丁烯-苯乙烯三嵌段共聚物(SEBS)作增容剂,用2种方法制备LDPE/PS共混物,均对混合物分散相颗粒尺寸和形态有影响,主要是由于界面现象,而不是流变行为,同时还计算SEBS/LDPE以及SEBS/PS共混物的相互作用能密度β,试验表明,随着SEBS中EB体积分数的增加,SEBS/LDPE共混物的β值减小,而SEBS/PS共混物的β值增加,并在EB体积分数约0.45时两条曲线相交。  相似文献   

2.
以苯乙烯-乙烯/丁烯-苯乙烯三嵌段共聚物(SEBS)作增容剂,用2种方法制备LDPE/PS共混物,均对混合物分散相颗粒尺寸和形态有影响,主要是由于界面现象,而不是流变行为。同时还计算了SEBS/LDPE以及SEBS/PS共混物的相互作用能密度β。试验表明,随着SEBS中EB体积分数的增加,SEBS/LDPE共混物的β值减小,而SEBS/PS共混物的β值增加,并在EB体积分数约0.45时两条曲线相交。还提出了含增容剂的二元共混物分布的3种模型,用2种方法制备的共混物的分布模型均属于结合型。  相似文献   

3.
本文通过DSC、振簧仪研究了聚氧化乙烯类表面活性剂作为增容剂对PVC/SBR共混物相容性的影响,并用扫描电镜(SEM)观察了PVC/SBR共混物中橡胶分散相的形态结构和尺寸变化。结果表明,在PVC/SBR共混物中加入适量的表面活性剂可明显改善两相的相容性,橡胶分散相尺寸随表面活性剂用量、液体石蜡用量的变化而变化。  相似文献   

4.
氯化乙丙橡胶胶增容PVC/SBS共混体系的研究   总被引:1,自引:0,他引:1  
以氯化乙丙橡胶(CEPDM)为相容剂,研究了SBS对PVC的共混增韧改性。结果表明CEPDM能明显改善SBS与PVC的相容性,使共混物中SBS颗粒尺寸明显减小,分布更均匀,共混物的tg内移,常常和低温下制品冲击强度增大。当PVC/SBS/CEPDM为80/20/6(质量比)时,共混物的常温缺口冲击强度为56.3kJ/m^2,低温(-20℃)缺口冲击强度为32.4kJ/m^2。  相似文献   

5.
用顺酐化EPDM增容的EPDM改性聚甲醛   总被引:3,自引:1,他引:3  
以顺酐化三元乙丙橡胶(MEPDM)为增容剂,研究了EPDM对聚甲醛(POM)的共混增韧生。结果表明,MEPDM能明显改善POM与EPDM的相容性,使共混物分散相尺寸明显减少,分布更均匀,熔点和结晶度降低,缺口冲击强度提高。当POM/EPDM/MEPDM(质量比)为85/9/6时,共混物的缺口冲强度为10.2kJ/m^2。  相似文献   

6.
马来酸酐接枝SBS增容PVC/SBS的研究   总被引:6,自引:0,他引:6  
马来酸酐接枝苯乙烯-丁二烯=苯乙嵌段共聚物(SBS)用MSBS代表,以它为增容剂,研究了SBS对聚氯乙烯(PVC0的共混增韧改性。结果表明:MSBS能明显改善SBS与PVC的相容必 分散相SBS相区尺寸明显减小,分布更均匀,共混物的玻璃化转变温度内移,常温和低温下缺口冲击强度增大。当PVC/SBS/MSBS为75:25:4时,共混物的常温缺口冲击强度为58.3kJ/m^2,低温(-20℃)缺口冲击  相似文献   

7.
PS/LLDPE/SBS共混体系的研究   总被引:2,自引:0,他引:2  
许承威  方征平 《塑料工业》1997,25(1):55-57,68
本文介绍机械共混法制备PS/LLDPE/SBS共混物,并对共混物的组成、相容性、形态的力学性能等进行了研究。由研究表明,LLDPE在增容剂SBS存在下对PS树脂起增韧改性作用,当SBS的质量分类为5%(以PS+LLDPE100份(质量)为基准),PS/LLDPE为85/15(质量比)时,共混体系的冲击强度最大,为4.5kJ/m^2,SBS在PS/LLDPE共混物中含量较少时,它主要分布在PS和LL  相似文献   

8.
粉末改性SBR对PVC的增韧作用   总被引:6,自引:0,他引:6  
研究了粉末改性SBR对PVC的增韧作用。用TEM、SEM和DSC对粉末改性SBR与PVC共混物进行了分析。发现粉末改性SBR对PVC有显著的增韧效果。当粉末改性SBR用量由5份增加到10份,共混物的冲击强度由10~20kJ/m2突然升高到85~100kJ/m2。这种突变是由改性SBR在PVC基体中的相形态由分散相转变为网状结构,导致共混物由脆性断裂过渡到韧性断裂造成的。DSC分析显示改性SBR与PVC部分相容。  相似文献   

9.
粉末生SBR对PVC的增韧作用   总被引:5,自引:0,他引:5  
王炼石  蔡彤Min 《塑料工业》1997,25(3):102-105,108
研究了粉末改性SBR对PVC的增韧作用,用TEM、SEM和DSC对粉末改性SBR与PVC共混物进行了分析,发现粉末改性SBR对PVC有显著的增韧效果。当粉末改性SBR用量由5份增加到10份,共混物的冲击强度由10-20kJ/m^2突然升高到85-100kJ/m^2。这种突变是由改性SBR在PVC基体中的相形态由分散相转变为网状结构,导致共混物由脆性断裂过渡到韧性断裂造成的。DSC分析显示改性SBR  相似文献   

10.
EPDM/PA高性能弹性体的增容机理   总被引:5,自引:0,他引:5  
研究了氯化聚乙烯(CPE)对三元乙丙橡胶/尼龙(EPDM/PA)共混体系的增容机理。Molau实验表明,在一定的共混温度下,共混时间越长,PA与CPE发生的化学反应越多。TEM照片显示,分散相颗粒由相互镶嵌的两种物质组成,二者之间有一定的过渡层;硫化使分散相与基质胶产生共交联;观察到了以微纤形式存在的分散相。SEM照片显示,硫化明显改善了分散相颗粒与基质胶的粘合。DSC的研究表明,该体系为典型的三  相似文献   

11.
相容剂对PS/PP共混合金混容形态和性能的影响   总被引:3,自引:0,他引:3  
研制了马来酸酯接枝聚丙烯相容剂,并将其用于聚苯乙烯/聚丙烯的共混改性;通过力学性能测试、透射电镜分析、差示扫描量热分析等方法研究了相容剂对PS/PP合金的混容形态和力学性能的影响。结果表明:相容剂的加入,使PS/PP由不相容的独立聚集的两相变为相畴很小的细分散相,共混高分子的链段运动也表现为趋于均相结构的运动方式。加入相容剂后共混材料的冲击强度有明显提高,拉伸强度也有所上升。相容剂的含量对性能也有较大影响,相容剂用量为8%时,力学性能最好,从DSC测试中可以看到此时共混物趋向均相体系;继续增大相容剂用量,合金的力学性能反而下降。  相似文献   

12.
Compatibilizing effects of ethylene/propylene (EPR) diblock copolymers on the morphology and mechanical properties of immiscible blends produced from recycled low‐density polyethylene (PE‐LD) and high‐density polyethylene (PE‐HD) with 20 wt.‐% of recycled poly(propylene) (PP) were investigated. Two different EPR block copolymers which differ in ethylene monomer unit content were applied to act as interfacial agents. The morphology of the studied blends was observed by scanning‐ (SEM) and transmission electron microscopy (TEM). It was found that both EPR copolymers were efficient in reducing the size of the dispersed phase and improving adhesion between PE and PP phases. Addition of 10 wt.‐% of EPR caused the formation of the interfacial layer surrounding dispersed PP particles with the occurrence of PE‐LD lamellae interpenetration into the layer. Tensile properties (elongation at yield, yield stress, elongation at break, Young's modulus) and notched impact strength were measured as a function of blend composition and chemical structure of EPR. It was found that the EPR with a higher content of ethylene monomer units was a more efficient compatibilizer, especially for the modification of PE‐LD/PP 80/20 blend. Notched impact strength and ductility were greatly improved due to the morphological changes and increased interfacial adhesion as a result of the EPR localization between the phases. No significant improvements of mechanical properties for recycled PE‐HD/PP 80/20 blend were observed by the addition of selected block copolymers.  相似文献   

13.
PP/PS/SEBS三元共混物的研究   总被引:10,自引:0,他引:10  
以PS、SEBS为改性剂对PP进行改性。加入PS,体系的强度和刚度得到提高,断裂伸长率和冲击性能下降,对其改变的原因采用SEM进行了结构分析;SEBS是PS的良好相容剂,也是PP很好的增韧剂。同时使用PS和SEBS,体系拉伸强度为24.4MPa,弯曲模量810.6MPa,冲击强度82.0J/m,熔体流动速率12.7g/10min。  相似文献   

14.
The mechanical, thermal, rheological, and morphological properties of polypropylene (PP)/polystyrene (PS) blends compatibilized with styrene–isoprene–styrene (SIS), styrene–butadiene–styrene (SBS), and styrene–butadiene–rubber (SBR) were studied. The incompatible PP and PS phases were effectively dispersed by the addition of SIS, SBS, and SBR as compatibilizers. The PP/PS blends were mechanically evaluated in terms of the impact strength, ductility, and tensile yield stress to determine the influence of the compatibilizers on the performance properties of these materials. SIS‐ and SBS‐compatibilized blends showed significantly improved impact strength and ductility in comparison with SBR‐compatibilized blends over the entire range of compatibilizer concentrations. Differential scanning calorimetry indicated compatibility between the components upon the addition of SIS, SBS, and SBR by the appearance of shifts in the melt peak of PP toward the melting range of PS. The melt viscosity and storage modulus of the blends depended on the composition, type, and amount of compatibilizer. Scanning electron microscopy images confirmed the compatibility between the PP and PS components in the presence of SIS, SBS, and SBR by showing finer phase domains. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 266–277, 2003  相似文献   

15.
In this article, we discuss the phase morphology, thermal, mechanical, and crystallization properties of uncompatibilized and compatibilized polypropylene/polystyrene (PP/PS) blends. It is observed that the Young's modulus increases, but other mechanical properties such as tensile strength, flexural strength, elongation at break, and impact strength decrease by blending PS to PP. The tensile strength and Young's modulus of PP/PS blends were compared with various theoretical models. The thermal stability, melting, and crystallization temperatures and percentage crystallinity of semicrystalline PP in the blends were marginally decreased by the addition of amorphous PS. The presence of maleic anhydride‐grafted polypropylene (compatibilizer) increases the phase stability of 90/10 and 80/20 blends by preventing the coalescence. Hence, finer and more uniform droplets of PS dispersed phases are observed. The compatibilizer induced some improvement in impact strength for the blends with PP matrix phase, however fluctuations in modulus, strength and ductility were observed with respect to the uncompatibilized blend. The thermal stability was not much affected by the addition of the compatibilizer for the PP rich blends but shows some decrease in the thermal stability of the blends, where PS forms the matrix. On the other hand, the % crystallinity was increased by the addition of compatibilizer, irrespective of the blend concentration. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42100.  相似文献   

16.
The mechanical properties and morphology of polypropylene/wood flour (PP/WF) composites with different impact modifiers and maleated polypropylene (MAPP) as a compatibilizer have been studied. Two different ethylene/propylene/diene terpolymers (EPDM) and one maleated styrene–ethylene/butylene–styrene triblock copolymer (SEBS–MA) have been used as impact modifiers in the PP/WF systems. All three elastomers increased the impact strength of the PP/WF composites but the addition of maleated EPDM and SEBS gave the greatest improvements in impact strength. Addition of MAPP did not affect the impact properties of the composites but had a positive effect on the composite unnotched impact strength when used together with elastomers. Tensile tests showed that MAPP had a negative effect on the elongation at break and a positive effect on tensile strength. The impact modifiers were found to decrease the stiffness of the composites. Scanning electron microscopy showed that maleated EPDM and SEBS had a stronger affinity for the wood surfaces than did the unmodified EPDM. The maleated elastomers are, therefore, expected to form a flexible interphase around the wood particles giving the composites better impact strength. MAPP further enhanced adhesion between WF and impact-modified PP systems. EPDM and EPDM–MA rubber domains were homogeneously dispersed in the PP matrix, the diameter of domains being between 0.1–1 μm. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:1503–1513, 1998  相似文献   

17.
Compatibilizing effects of styrene/rubber block copolymers poly(styrene‐b‐butadiene‐b‐styrene) (SBS), poly(styrene‐b‐ethylene‐co‐propylene) (SEP), and two types of poly(styrene‐b‐ethylene‐co‐butylene‐b‐styrene) (SEBS), which differ in their molecular weights on morphology and selected mechanical properties of immiscible polypropylene/polystyrene (PP/PS) 70/30 blend were investigated. Three different concentrations of styrene/rubber block copolymers were used (2.5, 5, and 10 wt %). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the phase morphology of blends. The SEM analysis revealed that the size of the dispersed particles decreases as the content of the compatibilizer increases. Reduction of the dispersed particles sizes of blends compatibilized with SEP, SBS, and low‐molecular weight SEBS agrees well with the theoretical predictions based on interaction energy densities determined by the binary interaction model of Paul and Barlow. The SEM analysis confirmed improved interfacial adhesion between matrix and dispersed phase. The TEM micrographs showed that SBS, SEP, and low‐molecular weight SEBS enveloped and joined pure PS particles into complex dispersed aggregates. Bimodal particle size distribution was observed in the case of SEP and low‐molecular weight SEBS addition. Notched impact strength (ak), elongation at yield (εy), and Young's modulus (E) were measured as a function of weight percent of different types of styrene/rubber block copolymers. The ak and εy were improved whereas E gradually decreased with increasing amount of the compatibilizer. The ak was improved significantly by the addition of SEP. It was found that the compatibilizing efficiency of block copolymer used is strongly dependent on the chemical structure of rubber block, molecular weight of block copolymer molecule, and its concentration. The SEP diblock copolymer proved to be a superior compatibilizer over SBS and SEBS triblock copolymers. Low‐molecular weight SEBS appeared to be a more efficient compatibilizer in PP/PS blend than high‐molecular weight SEBS. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 291–307, 1999  相似文献   

18.
Polyethylene terephthalate (PET) and polypropylene (PP) are incompatible thermoplastics because of differences in chemical structure and polarity, hence their blends possess inferior mechanical and thermal properties. Compatibilization with a suitable block/graft copolymer is one way to improve the mechanical and thermal properties of the PET/PP blend. In this study, the toughness, dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA) of PET/PP blends were investigated as a function of different content of styrene‐ethylene‐butylene‐styrene‐g‐maleic anhydride (SEBS‐g‐MAH) compatibilizer. PET, PP, and SEBS‐g‐MAH were melt‐blended in a single step using the counter rotating twin screw extruder with compatibilizer concentrations of 0, 5, 10, and 15 phr, respectively. The impact strength of compatibilized blend with 10 phr SEBS‐g‐MAH increased by 300% compared to the uncompatibilized blend. Scanning electron microscope (SEM) micrographs show that the addition of 10 phr SEBS‐g‐MAH compatibilizer into the PET/PP blends decreased the particle size of the dispersed PP phase to the minimum level. The improvement of the storage modulus and the decrease in the glass transition temperature of the PET phase indicated an interaction among the blend components. Thermal stability of the PET/PP blends was significantly improved because of the addition of SEBS‐g‐MAH. J. VINYL ADDIT. TECHNOL., 23:45–54, 2017. © 2015 Society of Plastics Engineers  相似文献   

19.
PA/PP/SEBS三元合金的结构与性能   总被引:9,自引:1,他引:9  
本文作者采用氢化SBS(SEBS)三嵌段热塑性弹性体增韧PA/PP共混体系,应用挤出反应技术在双螺杆挤出机内就地产生相容剂,可改善体系的相容性,从而获得了超高韧性的尼龙合金,还采用SEM和TEM技术研究了此类体系的形态结构特征,这些形态结构为进一步研究结构与性能关系提供了丰富的资料。  相似文献   

20.
Compatibilizing effects of diblock copolymer polystyrene-block-poly(ethylene-co-propylene) (SEP) on the morphology and mechanical properties of immiscible blends of poly(propylene) (PP) and polystyrene (PS) were investigated. Notched impact strength, yield stress, elongation at yield and Young's modulus were determined as a function of different weight ratios of PP and PS and different amounts of added SEP as well. Scanning electron microscopy revealed a two-phase morphology of PP/PS blends, which exhibit poor mechanical properties. Even 2,5 wt.-% of SEP added to PP/PS blends can improve the notched impact strength and elongation at yield compared to non-compatibilized PP/PS blends. 10 wt.-% of SEP compatibilizer converted the brittle PP/PS blend to quite impactresistant polymeric material. Mechanical properties were improved because of the morphological changes and increased interfacial adhesion as a result of SEP localization between PP and PS phases. An analysis of yield stress data in terms of theoretical models showed that yield stress values of binary PP/PS blends can be predicted with Nielsen's model.  相似文献   

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